{"chapter":{"doi":"10.7930\/J03F4MH4 ","identifier":"water-related-illnesses","number":"6","report_identifier":"usgcrp-climate-human-health-assessment-2016","sort_key":60,"title":"Climate Impacts on Water-Related Illnesses","url":"https:\/\/health2016.globalchange.gov\/water-related-illness"},"chapter_identifier":"water-related-illnesses","cited_by":[],"confidence":"Based on the evidence, there is high confidence that increasing frequency or intensity of extreme precipitation events will compromise recreational waters and sources of drinking water with pathogens, nutrients, and chemical contaminants from agricultural, wildlife, and urban sources.

There is consistent qualitative evidence that flooding associated with extreme precipitation events and storm surge results in loading of pathogens and nutrients to surface and groundwater (and drinking water distribution systems) through stormwater runoff and sewage overflows. However, other human and social factors modify risk, and there are no national-level studies upon which to draw conclusions regarding quantitative projections of increased exposure. Thus, the limited number of studies supports a medium confidence level that human exposure risk will increase due to changes in extreme events.","contributors":[],"evidence":"Extreme precipitation can mobilize pathogens, nutrients, and chemical contaminants from agricultural, wildlife, and urban sources. Waterborne illness and outbreaks from pathogens following heavy precipitation events have been well documented in multiple studies using both passive and active surveillance on a local and regional level.dba82efa-be61-4edd-af85-ee5e3ed07139,686b4c04-41ae-4e4f-b66d-c091a81fbf2b,b2f32879-6a7c-4f28-b53e-4e04a8aa0b1e,21e1cee8-0687-41e3-89f0-b6ccf4321f40,75de5138-1833-4aaa-8c2b-646287f3d33c,3e64a90d-f0c2-4f1a-a286-ce437bd95e60,0753011f-53bd-40b8-a4b9-f22040fe617f,662c61dc-9cc8-44ac-b867-053086299e68,74c63f7c-61a8-4f16-8107-302340e75bac Likewise, extreme precipitation events and subsequent increases in runoff are key climate factors that increase nutrient loading in freshwater and marine recreational waters, shellfish harvesting waters, and sources of drinking water, which in turn increases the likelihood of harmful cyanobacterial blooms that produce algal toxins.9224c0ef-9655-4335-a810-ce86baf5a502 The drinking water treatment process can remove cyanobacterial blooms; however, efficacy of the treatment processes may vary from 60% to 99.9%. Ineffective treatment could compromise water quality and may lead to severe treatment disruption or treatment plant shutdown.04e8c401-42e8-4f96-a1fc-98fcf05e240c,05f2b7a8-ce88-4e38-b426-917720b9c324,ef7ca73d-ff36-45d1-acfb-6941b4072a58,9224c0ef-9655-4335-a810-ce86baf5a502 More frequent and intense extreme precipitation events are projected for many regions in the United States as climate changes. Consistent, high-quality evidence from multiple studies supports a finding that increased runoff and flooding events are expected to increase contamination of source waters (for drinking water supply) and surface waters used for recreation, which may increase people’s exposure to pathogens and algal toxins that cause illness.030e3539-a620-441c-adb6-042db1a3fa6e,8c50c794-b09b-4215-b46c-6c24931faf6e,067c087d-ac72-448f-8a8f-c554d7897519,f60a6281-fa30-444d-9acd-0d132a6d1683,446ef7fa-5acc-45df-9247-b042fc1fac39,a7f52e54-2ce0-46fc-b0a2-60729757a8c0,a815bd0f-e3a7-4090-a35e-2f12381d9428,123e376c-79da-456f-96da-773e6f1e76ca,67a32928-4a0c-487d-9cd8-f442e47cb8ae,812fc19e-0fb3-4740-a4c7-bfef0e560666,3e34582d-ee92-45b3-9240-924ca5e98824,d4066a1c-799d-4b50-948b-ae6b71e19ad5,e4ad4655-b747-4844-9737-ee6da2650b39,603e74e7-cfae-45ff-bf78-4c38f32aa678 Other factors may modify these risks, such as increased air or water temperatures, residence time in the environment, lower water levels, or dilution.","files":[],"gcmd_keywords":[],"href":"https:\/\/data.globalchange.gov\/report\/usgcrp-climate-human-health-assessment-2016\/chapter\/water-related-illnesses\/finding\/exposure-risk-from-extreme-precipitation-events.json","identifier":"exposure-risk-from-extreme-precipitation-events","ordinal":"2","parents":[],"process":"The chapter was developed through technical discussions of relevant evidence and expert deliberation by the report authors at several workshops, teleconferences, and email exchanges. Authors considered inputs and comments submitted by the public, the National Academies of Sciences, and Federal agencies. For additional information on the overall report process, see Appendices 2 and 3.